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Date: Tue, 25 Mar 2014 09:23:03 -0700
From: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
To: Christoph Lameter <cl@linux.com>
Subject: Re: Bug in reclaim logic with exhausted nodes?
Message-ID: <20140325162303.GA29977@linux.vnet.ibm.com>
References: <20140311210614.GB946@linux.vnet.ibm.com>
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On 25.03.2014 [11:17:57 -0500], Christoph Lameter wrote:
> On Mon, 24 Mar 2014, Nishanth Aravamudan wrote:
> 
> > Anyone have any ideas here?
> 
> Dont do that? Check on boot to not allow exhausting a node with huge
> pages?

Gigantic hugepages are allocated by the hypervisor (not the Linux VM),
and we don't control where the allocation occurs. Yes, ideally, they
would be interleaved to avoid this situation, but I can also see reasons
for having them all be from one node so that tasks can be affinitized
and get the guarantee of the 16GB pagesize benefit.

Thanks,
Nish